Marine propulsion control system and a vessel containing such a marine propulsion control system

ABSTRACT

A marine propulsion control system for controlling a set of propulsion units carried by a hull of a vessel, said marine propulsion control system including an input command regulator for generating a desired delivered thrust by the propulsion units in the set of propulsion units, a set of control units, wherein each control unit is associated with a separate propulsion unit in said set of propulsion units, wherein each control units is arranged to control the delivered thrust of the associated propulsion unit depending on input control signals received by the control unit and vessel including such a propulsion control unit.

BACKGROUND AND SUMMARY

The invention relates to a marine propulsion control system. Theinvention more specifically relates to a marine propulsion controlsystem adapted to control a set of propulsion units each provided with acontrol unit for control of the delivered thrust by the propulsion unitand selection of gear in the case a gear unit is associated with thepropulsion unit. An input command regulator is provided in the marinepropulsion control system to generate inputs from a driver of thevessel. The invention particularly relates to a propulsion controlsystem adapted to control three or more propulsion units with a reducednumber of control levers.

Several propulsion control systems adapted to control a plurality ofpropulsion units with a reduced number of control levers, that is inputsignals from one control lever should be sufficient to control thedelivered thrust in the case the control lever is a throttle lever or tocontrol engagement of gears in the case the control lever is a gearselector of two or more propulsion units. Examples of such propulsioncontrol systems are presented in U.S. Pat. No. 6,872,106 and U.S. Pat.No. 6,751,533.

U.S. Pat. No. 6,872,106 relates to a propulsion control system having aplurality of propulsion units each being controlled by an associatedcontrol unit. The associated control unit receives input command signalsfrom control levers via a remote control central processing unit, whichcentral processing unit is configured to receive lever position datafrom sensors and correlate the lever position data with motor positiondata in order to directly control more than one motor from a singlelever. All the motors controlled by the same input lever will becontrolled in identical manner unless some error prevents correctcontrol of the motors.

U.S. Pat. No. 6,751,533 relates to a propulsion control system for avessel, which in a single embodiment described in relation to FIG. 4controls a plurality of motors by a single control head. Each throttlelever is connected to a control unit providing control over two motors.All the motors controlled by the same input lever will be controlled inidentical manner unless some error prevents. correct control of themotors. The control system according to U.S. Pat. No. 6,751,533furthermore provides for a synchronisation mode when a master controlunit commands a slave control unit to adapt its associated motor ormotors to the same percentage of throttle as the motor or motorsassociated with the master unit. The architecture of the control systemis such that there is no difference in configuration between the mastercontrol unit and the slave control unit. Each control unit may assumethe role of the slave or master depending on the control of the driver.Entry into synchronisation mode is made by setting the control levers ofboth control units into approximately the same position, where after oneof the control units assumes the role of the master control unit and theother assumes the role of the slave unit. In this mode the control leverof the throttle associated with the master control unit controls thethrottle of the motor associated with slave control unit such that bothmotors assumes the same throttle lever. The synchronisation mode doesnot obviate the need for a control lever for the slave unit since thisis a particular mode when the motors should have the same throttlelever. Thus independently of the whether the synchronisation node isassumed or not, all the motors controlled by the same input lever willbe controlled in identical manner unless some error prevents correctcontrol of the motors.

It is desirable to provide a marine propulsion control system whichenables an adapted control of a plurality of propulsion units controlledby a single input lever such that two propulsion units controlled by thesame lever may assume different levels of thrust depending on thedriving situation of the vessel.

An aspect of the invention contemplates to arrange least one controlunit in a set of control units provided in the control system to act asa slave control unit in all driving conditions and to receive its inputcontrol signals from one or several master control units in said set ofcontrol units to adapt the delivered thrust of the propulsion unitassociated with the slave control unit to the driving condition of thepropulsion unit or units associated with the master control unit orunits and in that said master control unit or units in all drivingconditions receives its input control signals directly from the inputcommand regulator. According to the invention, the slave control unit isalways assigned as a slave control unit and is therefore not connecteddirectly to an input command regulator arranged for generating a desireddelivered thrust by the propulsion units in the set of propulsion units.The slave control unit therefore receives control information from themaster control unit in all driving conditions and adapts the deliveredthrust of the propulsion unit associated with the slave control unit tothe input signal from the master control unit. The adaptation may bedifferent under different driving conditions as will be explained infurther detail below. For this reason, the slave control unit mayinclude a thrust control generator which generates a set value for itsassociated propulsion unit in dependence of the input signal from themaster control unit. The thrust control generator may be in the form ofa map or look up table which translates input signal into a requesteddelivered thrust level for the associated propulsion unit.

In an embodiment of the invention the input command regulatorfurthermore includes a gear selector for selecting forward, reverse orneutral position of gear units associated with the propulsion units,wherein each control units is furthermore arranged to control the gearselection of the associated gear unit depending on input control signalsreceived by the control unit, wherein the slave control unit or unitsare, in all driving conditions arranged to adapt the gear selection ofthe gear unit associated with the slave control unit to the drivingcondition of the propulsion unit or units associated with the mastercontrol unit or units and in that said master control unit or units inall driving conditions receives its input control signals directly fromthe input command regulator. By the adaptation of the gear selection ofthe slave control unit, it is for example possible to avoid the vesselto involuntarily increase the drift of the vessel toward one side in theevent one propulsion unit does not operate properly. Furthermore dockingand slow control of the vessel may be more easily achieved sinceengagement of forward and rear gears may be programmed to be delayed forpropulsion units associated with either the slave or master unitdepending on the situation or design of the vessel.

The system is particularly advantageous when the input command regulatorincludes a single starboard input command regulator and a single portinput command regulator and said set of control units includes twomaster control units including a single starboard master control unitand a single port master control unit and at least one slave controlunit. Preferably the slave control unit is associated with a propulsionunit positioned on the centre line of the hull and that said slavecontrol unit receives input control signals from both master controlunits.

The slave control unit may be arranged to engage the associated gearunit in neutral position unless both master control units has receivedinput command signals requesting to serve their respective gear units toengage either both in reverse or both forward gear, in which case theslave control unit is arranged to engage the associated gear unit in thesame gear as both gear units associated with the master units.

In the event both master control units has received input commandsignals requesting to serve their respective gear units to engage eitherboth in reverse or both forward gear, the slave control unit may bearranged to engage the associated gear unit in the selected gear at afirst lower level of delivered thrust and the master control units arearranged to engage their associated gear units in the selected gear at asecond higher level of delivered thrust.

In this event the first lower level preferably corresponds to zerothrust and that said second higher level is lower or equal to the numberof propulsion units controlled by the slave unit divided by the totalnumber of propulsion units in said set, where the higher levelpreferably corresponds to less than 10% thrust.

In a further preferred embodiment each slave control unit may be adaptedto control the delivered thrust from its associated propulsion unit toan average value of a first and second level of thrust indicated by thestarboard and port master control units respectively.

In another embodiment each master control unit is preferably associatedat least one slave control unit receiving input control signals solelyfrom the master control unit being associated with propulsion unitsarranged on the same side of the centre line as the propulsion unitassociated with the master control unit.

The slave control units may be arranged such that to each master controlunit is associated a slave control unit that receives input controlsignals from one master control unit only. In this system it ispreferred that the level of thrust associated with the slave unit is setto be equal to the level of thrust associated with the master unit.

The invention also relates to a vessel including a propulsion controlsystem as has been described above, which vessel includes three or morepropulsion units.

BRIEF DESCRIPTION OF DRAWINGS

An exemplifying embodiment of the invention will be described in greaterdetail below together with appended drawings where;

FIG. 1 shows a first embodiment of a marine propulsion control systemarranged to control three propulsion units,

FIG. 2 shows a second embodiment of a marine propulsion control systemarranged to control four propulsion units, and

FIG. 3 shows a graphic representation of a scheme for engagement anddisengagement of gears in gear units.

DETAILED DISCLOSURE

FIG. 1 shows a simplified top view of a vessel 1 in which the presentinvention can be used. Generally, the invention can be used in any typeof vessel, such as larger commercial ships, smaller vessel such asleisure boats and other types of water vehicles or vessels. Theinvention is particularly useful for small leisure boats, but it isnevertheless not limited to such type of water vehicle only.

As indicated schematically in FIG. 2, the vessel 1 is designed with ahull 2 having a bow 3, a stern 4 and being divided into two symmetricalportions by a centre line C. In the stern 4, three propulsion units 5, 6and 7 are mounted. More precisely, the vessel 1 is provided with a firstpropulsion unit 5 arranged at the port side, a second propulsion unit 6arranged at the starboard side and a third propulsion unit 7 arranged inthe centre. The propulsion units 5, 6 and 7 are pivotally arranged inrelation to said hull for generating a driving thrust in a desireddirection of a generally conventional kind, for example in the form ofan outboard drive, an azimuthal drive unit or out board engines.Pivotally arranged propulsion units of different types are known in theart, such as for instance out board engines arranged in the stern of thevessel, out board drive units pivotally arranged in relation to thehull, and which out board drive units are powered from a non rotatablyarranged power unit such as for instance of the type described inWO03093105 and azimuthal drive units where the propulsion unit togetherwith its power unit are pivotally arranged in relation to the vesselsuch as of the type described in U.S. Pat. No. 6,688,927, an willtherefore not be described in further detail. The control of thepropulsion units are performed by a marine propulsion control system 9.

The two propulsion units 5, 6 may advantageously be independentlysteerable by a steering control system cooperating with and preferablyintegrated into the propulsion control system 9. With independentlysteerable is intended that each propulsion unit is connected to andcontrollable by means of separate steering control units 10, 11 and 12which are suitably in the form of a computerized unit for receivingcommands from steering control instruments 13, 14. The steering controlinstruments may be provided in the form of a steering wheel 13 or a joystick 14 or the combination of both.

The invention also applies to propulsion units that are locked in afixed direction used on vessels steered by rudders in stead of pivotallyarranged propulsion units.

The separate steering control units 10-12 may be integrated in a set ofcontrol units 15-17 included in the propulsion control system 9, whereeach control unit 15-17 is associated with a separate propulsion unit5-7 in the set of propulsion units provided on the vessel. Each controlunits 15-17 in the set of control units is arranged to control thedelivered thrust of the associated propulsion unit depending on inputcontrol signals received by the control unit.

An input command regulator 18 includes means for generating a desireddelivered thrust by the propulsion units in the set of propulsion unitsis arranged in the marine propulsion control system. The input commandregulator may for this purpose include a port throttle lever 19 a, and astarboard throttle lever 19 b arranged to generate a desired deliveredthrust by the propulsion units contributing to the thrust on thestarboard and port side respectively. Each levers generates inputcontrol signals to an assigned master control unit 15, 17 respectivelywhile the centre control unit 16 acts as a slave unit and receives itsinput control signals from both master control units 15, 17.

The master control units 15, 17 furthermore receives input signal from agear selector 20 arranged in the input command regulator 18 which gearselector 20 serves to control respective gear unit 21 a-21 c associatedwith the propulsion units to be engaged in reverse, neutral or drive.Preferably two gear selectors 22 a, 22 b are provided. One for eachgroup of propulsion units positioned on the starboard side of the centreline and one for the group of propulsion units positioned on the portside of the centre line.

Such gear selector and throttle lever units are previously known assuch, and for this reason they are not described in detail here. Basedon received information from the steering control instruments 13, 14,the control units 15-17 are arranged to control the propulsion units 5-7in a suitable manner to propel the vessel 1 with a requested directionand thrust.

Preferably the input command regulator 18 includes a single starboardinput command regulator and a single port input command regulator foreach function that is under control by the input command regulator. Ashave been explained above, these functions may include port andstarboard throttle levers and port and starboard gear selectors. andsaid set of control units includes two master control units including asingle starboard master control unit and a single port master controlunit and at least one slave control unit.

The position of the propulsion units 5, 6 and 7 may be individuallycontrollable such that they may pivot and assume intended directions forgenerating a thrust in a desired direction independently of each other.Respective control unit controls actuator means 13, 14, which may forinstance be constituted by a stepping motor or a hydraulic circuit. Thesteering control units 10,11, 12 contains means for mapping an inputsignal from the steering control instruments into a reference valueangle for respective propulsion unit 5, 6, 7 where the actuator means 23a-23 c are arranged to move the propulsion units such that they assumesthe reference value angle. The mapping may be of simple type such that asteering angle is obtained from the steering control instruments andthat the actuator means uses this input signal as the reference valueangle. The mapping may also be more complex such that the referencevalue angles are calculated in dependence of the driving situationincluding speed, desired trim angle, whether docking is performed suchthat crabbing (movement in the sideways direction) of the vessel isdesired and so forth.

As has been explained above the master control units 15, 17 receivesinput signals directly from the input command regulator 18, while theslave control unit 16 receives input command signals from, in this caseboth master control units 15, 17. This applies in particular to thecontrol of gear selection and applied thrust by the propulsion units,while the steering control may be directly applied to the steeringcontrol unit 12 arranged in the slave control unit 16.

FIG. 2 shows a similar system as I FIG. 1, with the difference that thevessel includes four propulsion units which are controlled by master andslave control units each controlling an assigned propulsion unit. Herethe slave control unit only receives input signals from one of themaster control units. That is the slave control unit 16′ controls afirst port side propulsion unit P1 by using information provided from aport side master control unit 15′.

Furthermore, the slave control unit 16″ controls a first starboard sidepropulsion unit P2 by using information provided from a starboard sidemaster control unit 17′.

FIG. 3 shows a graphic representation of a scheme for engagement anddisengagement of gears in gear units controlled by two master controlunits and a slave control unit. In the event both master control units15,17 has received input command signals requesting to serve theirrespective gear units 21 a,21 c to engage either both in reverse or bothforward gear, the slave control unit 16 is arranged to engage theassociated gear unit 21 b in the selected gear at a first lower level L1of delivered thrust and the master control units 15,17 are arranged toengage their associated gear units 21 a, 21 c in the selected gear at asecond higher level L2 of delivered thrust. In a preferred embodimentthe first lower level L1 corresponds to zero thrust and the secondhigher level L2 is lower or equal to a proportion of the maximum ofrequested thrust equal to the number of propulsion units controlled bythe slave unit divided by the total number of propulsion units in saidset, that is L2=number of propulsion units controlled by the slavecontrol unit/total number of propulsion units.

In a preferred embodiment of the invention where the slave control unit16 controls a propulsion unit positioned in the centre is dependent oninformation from a port master control unit 15 and a starboard mastercontrol unit 17, the slave control unit 16 is adapted to control thedelivered thrust Tslave from its associated propulsion unit 7 to anaverage value of a first and second level of thrust TMaster1, TMastersindicated by the port and starboard master control units 15, 17respectively.

1. A marine propulsion control system for controlling a set ofpropulsion units carried by a hull of a vessel, the marine propulsioncontrol system including an input command regulator for generating adesired delivered thrust by the propulsion units in the set ofpropulsion units, a set of control units, wherein each control unit isassociated with a separate propulsion unit in the set of propulsionunits, wherein each control unit is arranged to control delivered thrustof the associated propulsion unit depending on input control signalsreceived by the control unit, wherein at least one control unit in theset of control units is arranged to act as a slave control unit in alldriving conditions and to receive its input control signals from one orseveral master control units in the set of control units to adapt thedelivered thrust of the propulsion unit associated with the slavecontrol unit to a driving condition of the propulsion unit or unitsassociated with the master control unit or units and the master controlunit or units in all driving conditions receives its input controlsignals directly from the input command regulator, wherein the inputcommand regulator includes a single starboard input command regulatorand a single port input command regulator for each function that isunder control by the input command regulator and the set of controlunits includes two master control units including a single starboardmaster control unit and a single port master control unit and at leastone slave control unit.
 2. A marine propulsion control system accordingto claim 1, wherein the input command regulator includes a gear selectorfor selecting forward, reverse or neutral position of gear unitsassociated with the propulsion units, wherein each control unit isfurthermore arranged to control gear selection of the associated gearunits depending on input control signals received by the control unit,wherein the slave control unit or units are, in all driving conditions,arranged to adapt the gear selection of the gear unit associated withthe slave control unit to the driving condition of the propulsion unitor units associated with the master control unit or units and the mastercontrol unit or units in all driving conditions receives its inputcontrol signals directly from the input command regulator.
 3. A marinepropulsion control system according to claim 1, wherein the slavecontrol unit is associated with a propulsion unit positioned on thecenter line of the hull and the slave control unit receives inputcontrol signals from both master control units.
 4. A marine propulsioncontrol system according to claim 3, wherein the slave control unit isarranged to engage the associated gear unit in neutral position unlessboth master control units has received input command signals requestingto serve their respective gear units to engage either both in reverse orboth forward gear, in which case the slave control unit is arranged toengage the associated gear unit in the same gear as both gear unitsassociated with the master units.
 5. A marine propulsion control systemaccording to claim 4, wherein, in the event both master control unitshas received input command signals requesting to serve their respectivegear units to engage either both in reverse or both forward gear, theslave control unit is arranged to engage the associated gear unit in theselected gear at a first lower level of delivered thrust and the mastercontrol units are arranged to engage their associated gear units in theselected gear at a second higher level of delivered thrust.
 6. A marinepropulsion control system according to claim 5, wherein the first lowerlevel corresponds to zero thrust and that the second higher level islower or equal to a proportion of the maximum of requested thrust, theproportion being equal to the number of propulsion units controlled bythe slave control unit divided by the total number of propulsion unitsin the set.
 7. A marine propulsion control system according to claim 6,wherein the higher level corresponds to less than 10% thrust.
 8. Amarine propulsion control system according to claim 1, wherein eachslave control unit is adapted to control the delivered thrust from itsassociated propulsion unit to an average value of a first and secondlevel of thrust indicated by the starboard and port master control unitsrespectively.
 9. A marine propulsion control system according to claim1, wherein to each master control unit is associated at least one slavecontrol unit receiving input control signals solely from the mastercontrol unit being associated with propulsion units arranged on the sameside of the centre line as the propulsion unit associated with the slavecontrol unit.
 10. A marine propulsion control system according to claim1, wherein to each master control unit is associated a slave controlunit that receives input control signals from one master control unitonly.
 11. A marine propulsion control system according to claim 10,wherein the level of thrust associated with the slave control unit isset to be equal to the level of thrust associated with the mastercontrol unit.
 12. A vessel comprising a marine propulsion control unitaccording to claim 1 and a propulsion unit controlled by each controlunit in the set of control units.
 13. A vessel according to claim 12,wherein the vessel is provided with three or more propulsion units.